1. Field of the Invention
The present invention relates generally to an adjustable holder assembly for positioning and holding a part or component. More particularly, the present invention relates to adjustable holder assembly for positioning a vacuum chuck holding a semiconductor wafer for examination and testing.
2. Description of the Prior Art
Although adjustable holder assemblies including stages providing movement in X and Y planes are known in the art, they suffer from dead areas in which the chuck cannot either be positioned or its rotation is limited, the chuck is not fully supported in all areas, and positioning requires a series of interactive adjustments to bring the chuck to a desired position.
Thus, there is clearly a need for an adjustable holder assembly providing positioning into all desired areas with a minimum of interaction between adjustments in each plane.